void SwapEntityGroup <T>(int entityID, int fromGroupID, int toGroupID) where T : IEntityDescriptor, new()
{
DesignByContract.Check.Require(fromGroupID != toGroupID, "can't move an entity to the same group where it already belongs to");
var entityViewBuilders = ((EntityDescriptorInfo)EntityDescriptorTemplate <T> .Default).entityViewsToBuild;
int entityViewBuildersCount = entityViewBuilders.Length;
var dictionary = _groupEntityViewsDB[fromGroupID];
Dictionary <Type, ITypeSafeList> groupedEntityViewsTyped;
if (_groupEntityViewsDB.TryGetValue(toGroupID, out groupedEntityViewsTyped) == false)
{
groupedEntityViewsTyped = new Dictionary <Type, ITypeSafeList>();
_groupEntityViewsDB.Add(toGroupID, groupedEntityViewsTyped);
}
for (int i = 0; i < entityViewBuildersCount; i++)
{
IEntityViewBuilder entityViewBuilder = entityViewBuilders[i];
Type entityViewType = entityViewBuilder.GetEntityViewType();
ITypeSafeList fromSafeList = dictionary[entityViewType];
ITypeSafeList toSafeList;
if (groupedEntityViewsTyped.TryGetValue(entityViewType, out toSafeList) == false)
{
toSafeList = fromSafeList.Create();
}
entityViewBuilder.MoveEntityView(entityID, fromSafeList, toSafeList);
if (fromSafeList.UnorderedRemove(entityID) == false)
{
dictionary.Remove(entityViewType);
}
}
if (dictionary.Count == 0)
{
_groupEntityViewsDB.Remove(fromGroupID);
}
}
